Means for detecting stuffing box leakage



Dec. 8, 1959 N. s. KITTRELL ETAI.` 2,915,975

MEANS FOR DETECTING STUFFING Box LEAKAGE Fned may 15, 1957 United StatesPatent() MEANS FOR DETECTING ySTUFFING BOX LEAKAGE Norman G. Kttrell, ElCampo, and Herbert E. Pietschker, Alvin, Tex., assignors to Texaco Inc.,a corporation of Delaware Application May 15, '1957, Serial No. 659,428

2 Claims. (ci. 10s-z5) A This invention relates generally to amonitoring systern for well production equipment and more specificallyto means for detecting stuing box leakage in such equipment.

One of the common situations encountered in petroleum production is thelarge dispersion area of the petroleum leldA where production isunderway. Consequently, many eld accessories are unattended for lengthyperiods of operating time, being inspected only occasionally', due tothe distances involved and the problem of manpower requirements for morefrequent observation. In many instances, the production of a eld may` bemarginal, due either to the depth of the wells or to the condition ofthe producing levels, or a combination of both, so that any unwarrantedloss of production uid leading to inefficient operation may result iniinancial troubles. Among the general sources of losses, in addition tobreakage of and leakage in the production lines, is that of leakage atthe stuffing box surrounding the polished rod of the pumping unit at thewell head.

If such leakage is not curbed promptly, it may reach excessive levels,as the wear by the action of the polished rod increases fromcontinuation of the pumping operation. Since some leakage from thestuing box is inevitable until it is discovered and the conditioncorrected, it is highly desirable to collect the leaking fluid in acontainer for salvage, and when the fluid level in the container reachesa certain calibrated point, to activate some kind of signal to indicatethe existing conditions, in order that proper action may be taken toremedy the situation, e.g. stopping of further pumping until thestuffing box is repacked. In this manner, the detection of stutiing boxleakage is possible at an early period, and at the same time, salvage ofvthe uid leakage provides economy of production.

Accordingly, it is an object of the present invention to provide meansfor detecting stutling box leakage.

It is another object of the invention to provide means by which stuffingbox leakage may be used to control the operation of the pumping unit atthe well head.

Still another object of the invention is to provide means by which theleakage from stufling box may be salvaged to prevent loss of productionfluid.

Still another object of the invention is to provide a means by -whichineiiicient operation of a pumping unit may be indicated.

And another object of the invention is to provide means for controllingthe operation of a pumping unit which is subject to stuing box leakage.

These and other objects and advantages of the invention will be apparentfrom the following specification when read in the light of the drawingsin which:

Fig. 1 is a diagrammatic showing of a part of a monitoring system forwell production equipment in which the present invention is used; and

Fig. 2 is an enlarged view of part of the equipment used in the salvageof stuffing box leakage.

The objects of the invention are attained by a means 2,915,975 PatentedDec. 8, 1959 ICS for collecting stuiiing box leakage, inwhich, after theleakage liquid has reached a calibrated point, there is an actuatingmeans brought into play for further control of the pumping unitinvolved.

Referring to Fig. 1 of the drawing, there is; disclosed a pumping unitA, located at the well head in a production field, a controller B,located nearby, and a central monitor control C, located relativelydistant from the production eld.

The pumping unit at A includes a prime mover or power plant 10, whichmay be either a gas engine or an electric motor. This provides the powerfor impartinga reciprocating motion to the sucker rod string, located inthe well, through the horse head walking beam at 1,1-, having theconventional horse head at 12, and counterbalance weights at 13. Fromthe horse head at 12, there extends the bridle 14, which is joined tothepolished rod 15. This rod extends through the salvage chamber or oilsaver unit 16, mounted on the stutiing box 17, which is supported by thecasing head 18. This casing head supports the casing string 19projecting into the well, indicated at 20'.

Fig.V 2 is an enlarged view of the salvage chamber 16, through which;the polished rodl 15 extends, with the double Vheaded" arrow indicatingits reciprocating motion. The chamber for the leakage fluid is dened bythe wiper O-ring at 15', which, with the packing glands, retains thefluid leaking past them into the chamber atop the stuffing box.

Referring to Fig. 1 again, from the salvage chamber 16, there is anoutlet conduit 21 which leads oi the leakage fluid, as indicated by thellow arrows, to a collecting chamber at 22, shown positioned under theSampson posts 23 of the pumping unit. There are disclosed an overflowoutlet at 24 and a drain outlet at 25, leading from the collectingchamber 22 and being joined to the drain 26 which leads to a sump (notshown). The operations of these outlets are controlled by solenoidoperated valves, indicated at 27 and 28 respectively. The collectingchamber has installed at 29 a control switch, of conventional type usedin the industry, and may be either oat or pressure operated. When thelevel of the leakage fluid in the collecting chamber reaches apredetermined or calibrated point and actuates the switch, a signalpasses along the conductor lin-e 30 to the controller B.

Depending upon the predetermined situation and outcome desired, anappropriate signal may be delivered by the conductor line 31 to closedown the prime mover at 10, and/or a supervisory signal may be passedalong by the conductor line 32 to the central monitor control of anautomatic control system at C, where the location and type ofmalfunctioning is indicated, so that proper repairs may be initiated.Thereafter, a control signal may be returned from the central monitorcontrol by the conductor line 33 to the controller B. This signal may inturn cause another signal to be delivered by the conductor line 31leading from the controller B to the prime mover 10, either to closedown the unit from further pumping action, if it has not been stoppedpreviously, or to start up the unit to resume pumping. The signaldelivered by the conductor line 33 to the controller B also may be ofsuch a nature as to cause the solenoid operated valves at 27 and 28 tobe actuated selectively, by means of the conductor lines 34 and 35respectively, which may result in opening the valves for a partial orcomplete drain-off from the collecting chamber of the leakage uid.

Thus, it can be seen that an apparatus in which the signal from theswitch at 29 is delivered to the controller B, and in turn, may bepassed on to the central monitor control C, has been developed fordetecting stuliing box leakage automatically, without necessity offrequent personal inspections, and that such apparatus can be used forcontrolling the` production in an eicient manner, not

Yand providing power thereto, and a stuiiing box having packingv glandssurrounding said polished rod, the combination therewith of meansvforindicating leakage at said stuing box 1 comprising a chamberV joinedthereto and surrounding said rod for receiving production liuid leakingpast said packing glands, means for collecting leakage fluid fromY saidchamber connected thereto, means for indicating a predetermined level ofcollected leakage liuid and thereby leakage of a known amount bytransmission ofa signal joined to said last mentioned means, meansinterconnecting suchv indicating means with said pumping Y Y unit forthe control of the latter in response to said signal wherebytheoperation of said prime mover may be l'governed,'said means forcollecting leakage uid having a drain outlet, and means for governingthe operation of said drain outlet joined thereto and interconnectedwith said means for the control of said pumpingunit.

2. A monitor set-up` for a pumping wellfor signaling a control stationof an-automatic control system of the existence of stu'ing box leakageat a specific location comprising, in combination, a pumping unitincluding a prime mover therefor, a polished rod interconnectedtherewith, and a stuing box having packing glandssurrounding said rod ata-well head, means for collecting iluidlleakage past said packing glandscomprising a salvage-chamber'mounted in series with said stuing box andsurrounding said rod, means joined to said salvage chamber for receivinguid leakage therefrom comprising a collecting chamber having acontrolledrdrain outlet, lmeans joined to said collecting chamberresponsive to said uid leakage when a predetermined amount thereof hasaccumulated therein comprising a control switch whereby a signal Yistransmitted to indicate the existence of stufling box leakage forfurther control of said pumping unit, and control means for receivingsaid signal and for maintaining a predetermined amount of leakage fluidin said collecting Vchamber interconnecting said last mentioned means,with said controlled drain outlet, and a monitor controlmeans joined tosaid last mentioned control means.

References Cited in the file of this patent 4 UNITED srATEsrATEN'rsA2,769,395 olsen Nov. 6,1956

